Functional dissection of circuitry in a neural integrator Academic Article uri icon


MeSH Major

  • Action Potentials
  • Models, Neurological
  • Nerve Net
  • Neurons
  • Ocular Physiological Phenomena


  • In neural integrators, transient inputs are accumulated into persistent firing rates that are a neural correlate of short-term memory. Integrators often contain two opposing cell populations that increase and decrease sustained firing as a stored parameter value rises. A leading hypothesis for the mechanism of persistence is positive feedback through mutual inhibition between these opposing populations. We tested predictions of this hypothesis in the goldfish oculomotor velocity-to-position integrator by measuring the eye position and firing rates of one population, while pharmacologically silencing the opposing one. In complementary experiments, we measured responses in a partially silenced single population. Contrary to predictions, induced drifts in neural firing were limited to half of the oculomotor range. We built network models with synaptic-input thresholds to demonstrate a new hypothesis suggested by these data: mutual inhibition between the populations does not provide positive feedback in support of integration, but rather coordinates persistent activity intrinsic to each population.

publication date

  • April 2007



  • Academic Article



  • eng

PubMed Central ID

  • PMC2803116

Digital Object Identifier (DOI)

  • 10.1038/nn1877

PubMed ID

  • 17369822

Additional Document Info

start page

  • 494

end page

  • 504


  • 10


  • 4